Once again, 130,000 pop-culture enthusiasts will descend on San Diego beginning July 18, immersing themselves in their favorite movies, TV and other pastimes for Comic-Con International, turning the sprawling convention into the center of the media universe.Yet while the annual gathering is generally characterized by fans enthusiastically interacting with celebrities, a darker side of fandom has been in the headlines of late, reflecting the sort of distasteful minority that can give fans a bad name — and might eventually prompt some talent to think twice about how much exposure they want to that culture.In June, "Star Wars: The Last Jedi" co-star Kelly Marie Tran made headlines by deleting her Instagram posts, responding to racist and misogynistic trolling that chased her from those platforms. Her decision follows Daisy Ridley's exit from Instagram in 2016 after she spoke out against gun violence, as well as the venomous rhetoric directed at Leslie Jones that year when the all-female version of "Ghostbusters" produced a jarring level of online vitriol, prompting her to temporarily leave Twitter.Such hate-filled voices likely represent a small portion of the fan community, as "Last Jedi" director Rian Johnson noted, saying via Twitter, "On social media a few unhealthy people can cast a big shadow on the wall, but over the past 4 years I've met lots of real fellow SW fans. We like & dislike stuff but we do it with humor, love & respect. We're the VAST majority, we're having fun & doing just fine."Still, as Luke Holland wrote in the Guardian, there is a "poisonous tributary of fanboyism that appears again and again," with an "ugly pattern of concerted attacks on diversity and representation" within high-profile science fiction and fantasy properties.For studios, Comic-Con remains a prime venue, and a valuable way of stoking interest in upcoming projects by turning the most avid fans into ambassadors for them. The lure of early glimpses and previews of eagerly awaited fare creates a multiplier effect that offers the potential of a viral return on their marketing dollars.Granted, some studios have reduced their presence at the convention, but that's largely based on other concerns, from leaked footage to the ebb and flow of releases aimed at fan communities.It's unfair for fans to be judged by their most extreme quadrants, and there's no obvious way to police such behavior. But the unsettling nature of certain voices has highlighted the myopic sense of entitlement that some fans harbor regarding certain franchises, as if their commitment patronage allows them to dictate the paths that are pursued creatively.Recent events have called attention to a strain of fandom that crosses into uncomfortable territory. Nitpicking minutia is one thing (and frankly, part of Comic-Con's charm), while dealing with abusive jerks is entirely another.As it stands, the sour taste associated with online harassment doesn't appear to have dampened enthusiasm in Comic-Con, which remains circled on the calendar as the foremost showcase of its kind.Thanks to social media, however, the few bad apples have become harder to ignore. That means the well-intentioned fans among the colorful array of superheroes, Jedi and wizards crowding together to enjoy Comic-Con must endure, like it or not, a peripheral association with the malcontents, cranks and trolls.